我有一个像这样的数据框:
import pandas as pd
import numpy as np
date_rng = pd.date_range(start="2023-11-18", periods=3, freq="10S")
values = [4, 2, 3]
df = pd.DataFrame(data={"values": values}, index=date_rng)
df["dt"] = df.index.to_series().diff().dt.seconds
df["dt"] = df.index.to_series().diff(periods=2).dt.seconds
df["dt_neg"] = df.index.to_series().diff(periods=-1).dt.seconds
print(df)
给予
values dt dt_neg
2023-11-18 00:00:00 4 NaN 86390.0
2023-11-18 00:00:10 2 NaN 86390.0
2023-11-18 00:00:20 3 20.0 NaN
负值不也应该起作用吗?